Class: ActiveRecord::Write

Inherits:
Object
  • Object
show all
Defined in:
lib/active_record/write.rb,
lib/active_record/write/version.rb

Constant Summary collapse

DEFAULT_SIZE = 
24
DEFAULT_SERIALIZER = 
::JSON
EMPTY_HASH = 
{}
VERSION = 
"1.1.2"

Instance Method Summary collapse

Constructor Details

#initialize(query:, columns:, target:, size:, serializer:, &transaction) ⇒ Write

‘query` is either an ActiveRecord query object or arel `columns` is a list of columns you want to have during the transaction `target` is the table you want to talk to `size` is the maximum number of running iterations in the pool, default: 24 `serializer` is the #dump duck for Array & Hash values, default: JSON `transaction` is the process you want to run against your database



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# File 'lib/active_record/write.rb', line 21

def initialize(query:, columns:, target:, size:, serializer:, &transaction)
  @query = query
  @columns = columns
  @target = target
  @size = size
  @serializer = serializer
  @transaction = transaction
  @table = Arel::Table.new(@target)
  @queue = case
  when activerecord?
    @query.pluck(*@columns)
  when arel?
    ActiveRecord::Base.connection.execute(@query.to_sql).map(&:values)
  when tuple?
    @query.map { |result| result.slice(*@columns).values }
  when twodimensional?
    @query
  else
    raise ArgumentError, 'query wasn\'t recognizable, please use some that looks like a: ActiveRecord::Base, Arel::SelectManager, Array<*Hash>, Array<*Array>'
  end
  puts "Migrating #{@queue.count} #{@target} records"
end

Instance Method Details

#pool(qutex = Mutex.new) ⇒ Object 



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# File 'lib/active_record/write.rb', line 44

def pool(qutex = Mutex.new)
  # Spin up a number of threads based on the `maximum` given
  1.upto(@size).map do
    Thread.new do
      loop do
        # Try to get a new queue item
        item = qutex.synchronize { @queue.shift }

        if item.nil?
          # There is no more work
          break
        else
          # Wait for a free connection
          ActiveRecord::Base.connection_pool.with_connection do
            ActiveRecord::Base.transaction do
              # Execute each statement coming back
              Array[instance_exec(*item, &@transaction)].each do |instruction|
                ActiveRecord::Base.connection.execute(instruction.to_sql)
              end
            end
          end
        end
      end
    end
  end.map(&:join)
end